Some of the instruments which tell commanders about the state of the nuclear reactor were also feared compromised, the Guardian can reveal. The detectors which measure the power coming from the reactor are in a lead-lined water jacket that surrounds the reactor core.
The lead has to be “virgin” metal, mined from great depth, so that it does not carry any electrical charge of its own that could generate a false reading.
However, the lead used in Astute was not of the right quality, which means instruments gave incorrect readings. Using impure lead can also have a knock-on effect during maintenance – the charged metal can create increased and persistent radioactivity within the reactor compartment.
I’m really not sure what is being said there at all.
You might want “deep mined virgin lead” to get away from having contamination with the residues of atmospheric testing of nuclear bombs. Or you might want to have lead which itself is not radioactive. In which case you don’t want virgin lead at all. You want old recycled lead. The stuff stripped off medieval churches is good for this. For the lead-210 present in all newly made lead will have decayed.
But I’m really not sure how that could lead to “electrical charges”. Anyone actually know this area and care to explain it to us?